Fog nozzle



Feb. 28, 1950 T. w. BURNAM 2,499,092

FOG NOZZLE Filed May 1.4, 1946 Patented Feb. 28, 1950 FOG NOZZLEpartnership Application May 14,1945, S erial l\lo..,i69,522 I Thisinvention relates to fog nozzles of the type employed in extinguishingfires.

The general object of the present invention is to provide an efficientform of fog nozzle of the internal impinging type.

For the purpose of extinguishing fires, there have been developed andextensively employed, nozzles (sometimes installed as stationary heads)in which there are provided one or more sets of orifices which aredesigned to produce streams of fluid, which streams lay in intersectingpaths. The intersecting streams of fluid when the meet in a properlydesigned fOg nozzle result in the breaking up of the stream of fluidinto fine particles which are projected outwardly from the nozzle in theform of a. so-called fog pattern, in which the individual particles offluid are substantially uniformly dispersed. It has been found that suchfog patterns are highly effective means for extinguishing many types offire.

In most of the practical forms of fog nozzles,

the streams of water from the orifices are projected beyond the body ofthe nozzle before they are allowed to impinge one against the other, sothat the development of the fog takes place entirely exterior of thenozzle. In certain cases, however, it is desirable to provide nozzles inwhich the formation of the fog takes place substantially internally ofthe nozzle, and in which the impinging jets impinge inside rather thanexteriorly of the body of the nozzle.

Heretofore efforts to produce such internal type of impingement haveresulted in nozzles operatively in action on the external impingementtype, and are relatively ineflicient and unsatisfactory. The previousinternal impinging nozzles have the disadvantage of excessive drippingand inadequate breaking-up of the water into uniformly small particles,and inadequate production of the desired fog from the face of thenozzle.

It is the general object of the present invention to provide a fognozzle of the internal impingement type which is designed to overcomethe difliculties previously mentioned and is capable of effecting asatisfactory generation of fog which will be uniformly distributed in afog pattern properly projected away from the body of the nozzle withoutthe loss of any substantial portion of the water at the nozzle and dueto dripping.

The internal impingement nozzle of .the present inventionwill be fullyunderstood from the following description of a simple example of anozzle embodying the invention. For that purpose I have herein describedthe impingement type of nozzle in connection with the accompanyingdrawing, in which the figure is a longitudinal section.

Referring to the drawing, I have illustrated my invention in the form ofa nozzle which contains one set of impinging orifices, although thosefamiliar with the art of fog nozzles will know that while headsincluding only a single set of impinging orifices are employed, thereare also employed many heads containing a multiplicity of impingingjets.

In the figure, 2 indicates the body which may have the substantiallycylindrical walls indicated, which provide the fluid chambers 3. Thewalls may be threaded as indicated at 4 by means of which the fog nozzlemay be attached to any desired source of fluid.

The nozzle is provided with a head member 5 which is provided with twomain orifices 6 and bored along the converging paths, which pathsintersect as indicated at least mainly inside of the limits of the head5. When the orifices are arranged in the nozzle body as indicated,difflculty is experienced in the proper projection of a uniform fog awayfrom the face of the nozzle. A great im rovement in the performance ofthe nozzle is obtained by providing between any pairs of convergingorifices a small orifice, such as indicated at 1, preferablyperpendicular to the face of the head of the nozzle. This small boreprovides increased fluid pressure at a point which would otherwise bethe inside point of impingement of the two larger streams. In theabsence of the small bore, the nozzle has a tendency to produce a backressure at this point. causing dri ping, and cuttin down the properprojection of the nozzle. By adding the small bore. these difficultiesare overcome and the fog pattern is adequately projected away from thenozzle in a much improved manner.

The second feature utilized in overcoming the deficiencies heretoforedesigned in internal impingement nozzles, is in the use of thecounterbore indicated at 8. Iftwo orifices, such as 5, are bored asindicated in intersecting paths overlap a sharp wedge formed at themeeting surfaces of the orifices and at the exterior face of the nozzle,there will be an elliptical pattern generated. By counterboring, asindicated at 8, from the outer face, this elliptical formation ischanged into a circular discharge'hole and thereafter the Wedge shapedmeeting face of the orifices is removed and the two'flat surfaces 9provided. It has been discovered that with this arrangement thedifficulty heretofore encountered in the nozzle dripping issatisfactorily overcome. I

While the particular form of the fog nozzle herein illustrated is welladapted to carry out the objects of the present invention, it is to beunderstood that various changes and modifications may be made, and thisinvention includes the modifications and, changes that come within thescope of the appended claim.

I claim:

An internal impingement fog nozzle which includes a nozzle body having ahead with a plurality of converging orifices in said head, said orificesconverging in the direction of the exterior of the head and partiallywithin and partially outside the head, and a circular counterboreextending inwardly from the outer face of the head meeting the orificesat their points of intersection to provide a substantially circuliardischarge bore REFERENCES CITED The following references are of recordin the file of this patent:

UNITED STATES PATENTS Number Name Date 1,084,359 Potter Jan. 13, 19141,173,279 Kinney Feb. 29, 1916 1,569,448 Banner Jan. 12, 1926 2,323,464Glessner July 6, 1943

